Chemical Balance
When testing and adjusting spa water,you have two types of testing
methods to choose from:
The Reagent Test Kit:
is a method which provides a high level of accuracy. It is
available in either liquid or tablet form.
Test strips:
are a convenient testing method commonly used by spa
owners.
TA Scale
Balancing the Total Alkalinity
Total alkalinity (TA) is the measure of the total levels of
carbonates, bicarbonates, hydroxides, and other alkaline
substances in the water. TA can be considered a “pH buffer”. It
is the measure of the ability of the water to resist changes in
pH level.
The recommended total alkalinity is 80 - 120 ppm.
If the TA is too low, the
pH level will fluctuate widely from high to low. Low TA can be
corrected by adding an alkalinity increaser.
If the TA is too high, the
pH level will tend to be too high and may be difficult to bring
down. High TA can be corrected by adding an alkalinity
decreaser.
When the TA is balanced, it normally remains stable, although
adding water with high or low alkalinity will raise or lower the
TA level.
CH Scale
Balancing the Calcium Hardness
Calcium hardness (CH) is a measure of the total amount of
dissolved calcium in the water. Calcium helps control the
corrosive nature of the sp's water and is why soft water is not
recommended. The low calcium content of soft water is very
corrosive to the equipment and can cause staining of the spa
shell.
The recommended calcium hardness is 150 - 200 ppm.
If the CH is too low, add
a calcium hardness increaser.
If the CH is too high,
dilute the spa water with soft water.
When the CH is balanced, it normally remains stable, although
adding soft water or very hard water will raise or lower the CH
level.
pH Scale
Balancing the pH
The pH level is the measure of the balance between acidity and
alkalinity.
The recommended pH level is 7.2 to 7.6.
If the pH is too low, it
can cause corrosion of metal fixtures and the heating element.
Low pH can be corrected by adding a pH increaser.
If the pH is too high, it
can cause scaling by allowing metals or minerals to form
deposits and stain spa surfaces. High pH can be corrected by
adding a pH decreaser.
When the CH is balanced, it normally remains stable, although
adding soft water or very hard water will raise or lower the CH
level.